EARTH.COM - Ant bait does not erase an infestation the moment workers find it. The chemical must spread through a social colony, and that process takes time.
That delay can make the first few days hard to read. A drop in food searching may look like success, while a burst of roaming ants may look like failure.
New laboratory work on Argentine ants shows that two common bait ingredients can produce opposite behavior while most workers are still alive.
Boric acid pushed ants into dense groups inside the nest, while thiamethoxam sent many workers into the surrounding area.
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The research was conducted in the lab of Professor Dong-Hwan Choe at the University of California, Riverside (UCR).